Author Topic: Any Word on the Bullpup Kit  (Read 1662 times)

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Offline Manticore_Arms

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Re: Any Word on the Bullpup Kit
« Reply #15 on: June 10, 2019, 10:20:10 PM »

The only question is resetting the trigger since there is a little more mass with the trigger bar now.  I got your email and we can discuss.  :)

Sven
Manticore Arms

Sven, Art,

I just got one of Art's trigger kits... haven't installed it yet. I too am anxiously awaiting CZ's release of the kit. Please let us all know whether or not the 2-stage trigger has enough reset force to handle the bullpup trigger bar mass and friction.

I have seen some other bullpup kits that use a small spring to help reset the trigger bar. Say something about 1/2"-3/4" long with an initial preset of 1.5-2.5 oz and a very low spring constant (guessing in the 0.50-2.0 oz/in range). The question is, where would you put it?

DJ

edit: K units

The Bullpup EVO kit is not desgined for an additional reset spring, and Art and I believe, based on a good phone discussion, that his trigger kit will most likely work.  I have put him directly in touch with CZ USA so they can get him a production kit for testing as soon as they are ready.  That is about as much as we can do on it at this time to verify it will work.  ;)

Sven
Manticore Arms

Offline 3rdMAW

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Re: Any Word on the Bullpup Kit
« Reply #16 on: June 10, 2019, 11:34:21 PM »
Sven,

Thank you! That's great news.

DJ

Offline shootingsight

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Re: Any Word on the Bullpup Kit
« Reply #17 on: June 12, 2019, 12:29:10 AM »
My trigger spring falls between the HBI spring and the OEM spring in strength.  So if for some reason the system did not work with my trigger spring, the OEM could be used.

My concern is not really friction - it ought not be that high because none of the rubbing surfaces are loaded that high (as opposed to the sear surface that probably has 5 or 6 lb on it from the hammer spring).  The concerns I would want to look at are mass, as in how it would impact a drop test.  When a gun is dropped, mass on one side of the trigger pivot impacts to make the trigger turn in one direction, mass on the other side opposes it.  In the current trigger system, the imbalance is small enough that there is little tendency for the trigger to want to release when the gun is dropped.  Adding a mass of a linkage can change that, so it would bear examination and testing.

Offline 3rdMAW

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Re: Any Word on the Bullpup Kit
« Reply #18 on: August 17, 2019, 02:05:35 PM »
The concerns I would want to look at are mass, as in how it would impact a drop test.

I wonder if the delay in the release of the kit is due to this concern? I have a Bullpup Unlimited Remington 870 kit that has a trigger safety (a la Glock) for this very reason. The trigger bar will only move when your finger is pulling on the trigger safety/trigger. It cannot move if dropped with the external safety off. In the Manticore design it looks like it can. That worries me. I am sure this has been tested with the standard CZ springs and I am still going to buy the kit when it finally does come out... (just won't ever drop it with the crossbar safety off and lighter weight springs).

DJ Miller

Offline Manticore_Arms

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Re: Any Word on the Bullpup Kit
« Reply #19 on: August 18, 2019, 01:00:52 AM »
The concerns I would want to look at are mass, as in how it would impact a drop test.

I wonder if the delay in the release of the kit is due to this concern? I have a Bullpup Unlimited Remington 870 kit that has a trigger safety (a la Glock) for this very reason. The trigger bar will only move when your finger is pulling on the trigger safety/trigger. It cannot move if dropped with the external safety off. In the Manticore design it looks like it can. That worries me. I am sure this has been tested with the standard CZ springs and I am still going to buy the kit when it finally does come out... (just won't ever drop it with the crossbar safety off and lighter weight springs).

DJ Miller

It has nothing to do with that, drop testing was done a while ago.

Sven
Manticore Arms

 

anything